21201110111121 has 8 divisors (see below), whose sum is σ = 28268182179360. Its totient is φ = 14134055725152.

The previous prime is 21201110111117. The next prime is 21201110111141. The reversal of 21201110111121 is 12111101110212.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21201110111121 - 2² = 21201110111117 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21201110111121.

It is not an unprimeable number, because it can be changed into a prime (21201110111141) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1310260 + ... + 6642213.

It is an arithmetic number, because the mean of its divisors is an integer number (3533522772420).

Almost surely, 2^{21201110111121} is an apocalyptic number.

It is an amenable number.

21201110111121 is a deficient number, since it is larger than the sum of its proper divisors (7067072068239).

21201110111121 is an equidigital number, since it uses as much as digits as its factorization.

21201110111121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8841135.

The product of its (nonzero) digits is 8, while the sum is 15.

Adding to 21201110111121 its reverse (12111101110212), we get a palindrome (33312211221333).

Subtracting from 21201110111121 its reverse (12111101110212), we obtain a palindrome (9090009000909).

The spelling of 21201110111121 in words is "twenty-one trillion, two hundred one billion, one hundred ten million, one hundred eleven thousand, one hundred twenty-one".